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Invasive Mucormycosis: A Lesson
in the Need for Early Radiographic
Diagnosis
Control #: 1509
Excerpta #: EE-47
ASNR 2016 Annual Meeting
Nathan Wnuk, MD
Vaishali Phalke, MD
Jeffrey M. Pollock, MD
OHSU
Portland, OR
Disclosures
• No disclosures
Purpose
• To describe early imaging findings of
invasive mucormycosis
• To illustrate the importance of raising
suspicion for invasive mucormycosis when
imaging findings are present as the
condition can be clinically elusive
Case Report
Our patient is a diabetic 68-year-old male
with relapsed AML who was admitted in his
usual state of health for FLAG
chemotherapy.
• Developed neutropenic fever on day 8 of admission with
altered mental status.
• MRI of the brain was performed to evaluate for causes of
AMS
Imaging Findings - MR brain Day 8
• Is there any evidence of
fungal sinusitis on this
image?
Case Report
• Left periorbital swelling and mild visual changes
were noted on hospital day 12, but were
attributed to dependent edema and altered
mental status.
• The patient's condition deteriorated over the
next few days with worsened peri-orbital
swelling, vision changes and declining mental
status.
Case Report
• A fungal etiology was considered unlikely based
on
– repeat negative cultures
– sequential sinonasal endoscopies with no findings of
fungal disease
– sinus mucosal biopsy negative for fungal elements.
• Steroid nasal spray decongestion was started on
day 17 for suspected bacterial cellulitis/sinusitis.
Case Report
• The patient’s condition continued to worsen
• A CT of the sinuses was obtained on day 17 to
re-evaluate sinus disease
Imaging Findings – CT Day 17
• Showed bi-frontal edema with parenchymal hemorrhage
and worsened orbital inflammatory changes.
Case Report
• A follow-up MRI brain was obtained the same
day
Imaging Findings - MR Day 17
• intracranial invasion with extensive frontal lobe and
orbital involvement with diffusion restriction and
nonenhancement of affected areas.
Case Report
• The diagnosis of invasive mucormycosis was
confirmed on pathology via a transorbital biopsy
• Treatment with amphotericin B was initiated
• Unfortunately the patient succumbed to infection
the following day
Imaging review
Early findings
• Black turbinate sign
• No intracranial invasion
at this time
Late findings
• Intracranial invasion with nonenhancing and diffusion-restricting
brain parenchyma
Imaging review
Black turbinate sign:
– Mucormycosis is angioinvasive and
thrombogenic, causing devascularization of
tissue
– On contrast enhanced studies the
devascularized tissue appears black relative
to perfused enhancing tissue
Discussion
• Mucormycosis is a highly aggressive invasive
fungal infection that can be clinically devastating.
• Clinical diagnosis is made difficult by low
sensitivity of blood and tissue cultures for
identifying infection, with as many as 90% of
cases not confirmed until post mortem
examination.
Discussion
• Early diagnosis and recognition of initial subtle
imaging signs suggestive of the diagnosis may
allow for earlier treatment and improved patient
outcomes.
References
•
A. Katragkou, T.J. Walsh, E. Roilides, Why is mucormycosis more difficult to cure than more common mycoses?
Clinical Microbiology and Infection. 2014;20:74-81
•
Skiada, L Pagano, A Groll, et al. Zygomycosis in Europe: analysis of 230 cases accrued by the registry of the
European Confederation of Medical Mycology (ECMM) working group on zygomycosis between 2005 and 2007.
Clin Microbiol Infect. 2011;17:1859–1867
•
MM Roden, TE Zaoutis, WL Buchanan, et al. Epidemiology and outcome of zygomycosis: a review of 929 reported
cases. Clin Infect Dis, 2005;41:634–653